/*******************************************************************************
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 * 
 *     http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 ******************************************************************************/
package org.apache.nutch.api.resources;

import java.util.Iterator;
import java.util.Map;
import java.util.WeakHashMap;

import javax.ws.rs.Consumes;
import javax.ws.rs.POST;
import javax.ws.rs.Path;
import javax.ws.rs.core.MediaType;

import org.apache.nutch.api.impl.db.DbReader;
import org.apache.nutch.api.model.request.DbFilter;
import org.apache.nutch.api.model.response.DbQueryResult;

@Path("/db")
public class DbResource extends AbstractResource {

	private Map<String, DbReader> readers = new WeakHashMap<String, DbReader>();

	@POST
	@Consumes(MediaType.APPLICATION_JSON)
	public DbQueryResult runQuery(DbFilter filter) {
		if (filter == null) {
			throwBadRequestException("Filter cannot be null!");
		}

		DbQueryResult result = new DbQueryResult();
		Iterator<Map<String, Object>> iterator = getReader().runQuery(filter);
		while (iterator.hasNext()) {
			result.addValue(iterator.next());
		}
		return result;
	}

	private DbReader getReader() {
		String confId = ConfigResource.DEFAULT;
		synchronized (readers) {
			if (!readers.containsKey(confId)) {
				readers.put(confId,
						new DbReader(configManager.get(confId), null));
			}
			return readers.get(confId);
		}
	}
}
